If you mean credit notes, then I don’t think so. If you don’t get any or enough change you have to call for Help and explain. There will be a long wait while they poke the machine, get somebody more senior, who then pokes the machine before going off to get a key. Once it is opened, if the reason for the blockage is obvious, such as a bit of card in the wrong place, they say, “I don’t know how that got there”, in a tone suggesting that you have somehow managed to insert the card at the bottom of the column of coins, before finally handing over the due sum. If the reason is not obvious, you have to prod them to give you your money and not wait for someone to come from Taiwan to examine the machine.
I will say that the machines are not as bad as when they were new: you still get short changed occasionally, but they are less prone to fail to count some of the money you had inserted. I did once have a woman saying, “It is only 2p.” “Yes, but it is my 2p.”